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mikemopar

Towing The Heavy Load

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I’m in the market to purchase a 32’ diesel pusher to replace our 1999 30’ Arebus w/Ford V-10. We’re looking close at the used 32’ Itasca Meridian’s or similar which are usually equipped with the 300HP Cummings. We want to tow our 26’ (7500GVW) boat but questions have risen if the 300HP Cummings can make the grade. Would anyone have experience with this type of rig and its towing capacity? What may I expect on a 5 or 6% grade?
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Mikemopar,

I don't have experience with the 300 Cummins but did have an 8.3 liter Cummins, 1994 vintage. That engine as our current Cummins 400 was coupled with an Allison 6 speed automatic transmission. The 8.3 liter Cummins was pulling a little over 15 tons plus a toad of almost 6000 pounds. Our experience was that you could expect the engine to pull down on a 6% grade to a speed of 30 to 35 in third gear on a long 6% grade with that load. I don't know what your total GVW (Gross Vehicle Weight) will be but that might give you something to compare with.

Today our Cummins 400 ISL does about the same with our 16 ton motor home and the same toad. I don't consider that to be too bad a problem. With any large vehicle and the characteristics of the diesel engine, you will get about the same. I am usually able to pass the loaded trucks easily on such grades without straining the engine. More important, I have never encountered a grade that we couldn't climb with either engine.

Compare your weights to our vehicles and perhaps that will help you decide the capability of the engine/motor home you decide to finally purchase. Remember that a motor home is not a car and you will not find one that will perform or drive like a car. Travel in a motor home can be very relaxing if you go with the flow rather than trying to always get somewhere fast. Enjoy your journey!

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There are really two parts to the question.

First-- what is the coach rated to pull. And it is important to understand that LEAST STRONG component dictates towing capacity. That may be the hitch, transmission, brakes, frame (particularly if extended by the body builder), etc. Sadly, many people just look at the hitch rating, which can be very misleading. The same hitch can be used on a coach whose transmission is right at its GCWR or on one that is 12,000 pounds under its rating. It can be used on a coach with the hitch bolted to the frame or on one with a 6' frame extension. Etc, etc.

The second aspect, once you have verified that the coach can pull the weight, is to set reasonable expectations for coach performance.

Here is an excellent publication written by Caterpillar, but applicable to all heavy vehicles. It is entitled: "Understanding Coach (RV) Performance". There is a great section on HP required to climb 6% grades at different speeds.

https://ohe.cat.com/cda/files/287140/7/LEGT5364.pdf

Brett Wolfe

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Tom, Your intirely correct when you say you have to enjoy the journey.  This question on if the Cummings 300 is enough to "comfortably" tow a 7500lb trailer is a step to enjoying the journey.I saw a post for a 32' Itaska w/ the 300 Cummings and they advertised it to  have a 10,000 lb tow capicity.  Although I question that to be a comfortable tow.I own the Dodge CTD PU that does most all of the towing of the boat on our trips but we want to go cross country and would like the option of taking the RV.  The PU isn't effected on those 6% grades with the load.  In fact I can hold 60mph everywhere,  even after getting behind that 1973 Winny doing 25mph I can pass and recover back to 60mph in no time.Maybe I should re-state my question in asking, What do you have? How does it perform on a grade?What I have is;1999 30' Rexhall Arebus, ford V-10 w/BanksOn a 5% or 6% grade50MPH in 3rd gear by itself45MPH in 2nd gear towing the PT Cruiser40MPH in 2nd gear towing a 3500lb boat30-35MPH in 2nd gear towing a 7500lb boat, and creating alot of HEAT!Mike

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Just something to consider- I bought a d pusher as wlll but the problem is that the motor is in the back. Towing my 25 foot Mako is no problem, but as it turns out it is not a practicle vehicle to use to launch the boat on the ramp. hard to maneuber because of the MH legnth and since the engine is in the back- the very expensive diesel is the first thing to get wet if i get a boat wave, etc and the boat is so big that the engine is close to the water to get the trailer submerged. After rigging the mh- i decided to use my truck only to tow the boat. too much hastle and risk.

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I have a 34 Holiday Rambler 2006 with the 300 ISB and I tow a Saturn Vue which weighs about 3000 pounds. Most of the time I do not know I am pulling anything. And to be honest I don't know how much difference pulling the Saturn would make on a 6% grade. I do know that a long 6% grade slows me up from 60 to 40. I have never felt I was not going to make it as the transmission down shifts and just keept on "Truck'n". I drove from Phoenix to Flagstaff on I-17 and there are some long steep hills some 6% and I made it without problems. What I don't care for is going down steep grades and I am very thankful for the engine brake.

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Mike,

Saw the VN ribbon and just want to say "Welcome Home Brother"

Mikemopar,

I don't have experience with the 300 Cummins but did have an 8.3 liter Cummins, 1994 vintage. That engine as our current Cummins 400 was coupled with an Allison 6 speed automatic transmission. The 8.3 liter Cummins was pulling a little over 15 tons plus a toad of almost 6000 pounds. Our experience was that you could expect the engine to pull down on a 6% grade to a speed of 30 to 35 in third gear on a long 6% grade with that load. I don't know what your total GVW (Gross Vehicle Weight) will be but that might give you something to compare with.

Today our Cummins 400 ISL does about the same with our 16 ton motor home and the same toad. I don't consider that to be too bad a problem. With any large vehicle and the characteristics of the diesel engine, you will get about the same. I am usually able to pass the loaded trucks easily on such grades without straining the engine. More important, I have never encountered a grade that we couldn't climb with either engine.

Compare your weights to our vehicles and perhaps that will help you decide the capability of the engine/motor home you decide to finally purchase. Remember that a motor home is not a car and you will not find one that will perform or drive like a car. Travel in a motor home can be very relaxing if you go with the flow rather than trying to always get somewhere fast. Enjoy your journey!

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The key is the transmission. If the coach has a 6 speed Allison 3000 transmission, then it will be rated to tow 10,000 lbs. A

Allison 2500 series transmission will be rated for 5000 lbs. This per the 2005 Winnebago specs for a 32T Journey. The 32 ft Itasca is basically the same coach as the Winny 32T, with some upgraded stuff. I think that I remember that the Itasca has the 3000 series transmission, but I would check that. The 300hp Cummins in that small coach should get right along.

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you should have no problem I have a 34 ft expedition with 270 with banks system, I pull 26 ft enclosed trailer with trike honda goldwig and chev tracker plus what ever else I can stick in there. hope this helps

Doug

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Doug,

Without posting more information on your rig (transmission, GCWR, actual weights, etc) your advice may be misleading to the OP. Your rig may be very different mechanically from the rig he is considering. And a new buyer may not know all the relevant factors that determine safe towing limits and be able to translate from your rig to the one he is considering.

And we sure don't want to make recommendations on purchase based on a discussion of "I got away with ............." if it exceeds the manufacturer's recommendations.

Let's be safe out there.

Brett Wolfe

you should have no problem I have a 34 ft expedition with 270 with banks system, I pull 26 ft enclosed trailer with trike honda goldwig and chev tracker plus what ever else I can stick in there. hope this helps

Doug

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I have a Winny Journey with a Cummins ISB rated at 275hp, Allison 2000 tranny, 34ft long GVWR 24350, loaded weight more or less 21620#. Winny says 5000# trailer weight with 500 tongue weight OK.

I need to tow 6000# with 1700# tongue weight. Anyone have any suggestions as to how I can do it?

Anyone else with similar combination pulling loaded trailers? Please do not regurgitate the party line about safety and such, I need to know if anyone out there is "pushing it" and how.

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rbarkieyii,

My main concern would be the transmission. Check with Allison on max GCVW.

After that, you get into TWO issues:

1. The legal issue of what happens if you are in an accident. That is the one you suggested not to mention.

2. Physical issues involved with heavier toads. A good welder/home engineer may be your best bet.

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For reasons unknown to me Winnibago says you can not use a equalizer hitch of the Freightliner (Journey 34') chassis. I would like to use a equalizer to reduce tongue weight of trailer I want to pull. Anyone have any experience with Equilizer hitches on Journey or similar Freightliner chasis with air ride ect.

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For reasons unknown to me Winnibago says you can not use a equalizer hitch of the Freightliner (Journey 34') chassis. I would like to use a equalizer to reduce tongue weight of trailer I want to pull. Anyone have any experience with Equilizer hitches on Journey or similar Freightliner chasis with air ride ect.

Gosh I can't see why you could not use a equalizer unless it would overload the front axle of the coach and that may be the reason.

I would call Freightliner and ask. I have used a equalizer hitch many yrs ago when I pulled a camper trailer but not on a coach.

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I was going to suggest a call to Freightliner also but then realized they are going to tell you what you don't want to hear.

My 2008 XCS chassis hitch is rated for 10,000# with a 1000# tongue weight. It is a weight distribution hitch. What is the GCWR for your chassis? I think you would exceed tongue weight, tow weight and GCWR. As Brett suggested, find a home engineer to "design" a hitch because I don't think you will find any other engineer to sanction all your desires.

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